1. Field of the Invention
The present invention relates to a method of crystallizing a semiconductor thin film and, more particularly, to a method of crystallizing a semiconductor thin film, comprising melting the semiconductor thin film by irradiating the same with a laser beam emitted by a pulse laser.
2. Description of the Prior Art
A method of crystallizing a semiconductor thin film has been proposed which crystallizes a semiconductor thin film, such as an amorphous silicon hydride thin film (a-Si:H thin film) or an amorphous germanium hydride thin film (a-Ge:H thin film), for semiconductor integrated circuits by melting and solidifying the semiconductor thin film by irradiating the same with a laser beam emitted by a pulse laser. This known method has been a noticeable technique for fabricating thin film transistors with a high carrier mobility.
A method of forming a polycrystalline semiconductor thin film disclosed, for example, in Japanese Patent Laid-open No. Sho 64-76715 forms a polycrystalline semiconductor thin film by irradiating an amorphous silicon hydride semiconductor thin film formed on a glass substrate with a laser beam having a laterally trapezoidal intensity distribution. The use of such a laser beam avoids the deterioration in quality of the semiconductor thin film due to the rapid evaporation of hydrogen contained in the semiconductor thin film. However, this known method is not necessarily capable of forming a semiconductor thin film having satisfactorily electrical characteristics including high carrier mobility.